Renal sympathetic nerve activity has been identified as a contributor to hypertension, as patients with hypertension exhibit increased sympathetic activity relating to the kidneys. Ablation of renal nerves is one way of treating hypertension. In radio frequency (RF) ablation, RF energy is directed from the ablation electrode through tissue to ablate the tissue and form a lesion. Systems using other forms of energy, such as ultrasound, are also available for performing ablation.
Ablation has also been used in other applications. For example, ablation is one way of treating cardiac arrhythmias and restoring normal rhythm. The sources of aberrant electrical conduction are located, and the tissue is ablated.
Renal denervation and other catheter based ablation applications would benefit from real-time, active monitoring of tissue temperatures in the vicinity of the treatment target. Traditional temperature monitoring techniques that include wires which extend through the length of the catheter to a sensor at the catheter tip can adversely impact catheter performance and can be impractical. For example, the need to include a wire for each sensor adds bulk, stiffness, or diameter to the catheter affecting its size maneuverability, and possibly safe use. Conversely, the number of temperature sensors or monitoring points available in a catheter may be limited in order to maintain catheter functional characteristics. Wireless temperature monitoring technology for ablation catheter systems is described herein to mitigate limitations of traditional wired temperature sensors.